1. Field of the Invention
The present invention relates to a mechanism for adjusting a distance or a relative position between lens groups of an optical lens system and a camera equipped with the lens position adjustment mechanism.
2. Description of Related Art
Generally, in order for taking lens systems comprising a plurality of lens groups used for photographic camera such as conventional cameras for use with silver films and digital cameras to exhibit full optical performance, it is essential that lens groups of the taking lens system are precisely arranged with predetermined distances. If components of a taking lens, the lens groups and associated structural parts are manufactured as precisely meeting the dimensional specifications, the lens groups can be precisely arranged with the specified distances under ordinary circumstances when these components are assembled to a taking lens. However, because the components have manufacturing errors and variations as a matter of fact, it is necessary to adjust the manufacturing errors and variations in some way or other during assembling them to the taking lens so as thereby to relieve the manufacturing errors and variations collectively.
It is conventional to relieve the manufacturing errors and variations by using adjuster rings to fine adjust distances between lens groups. The adjuster ring is interposed between a lens holder in which a lens group is fixedly held and a lens barrel enclosing the lens holder, then the lens holder is continuously shifted back and forth with respect to the adjuster ring for a fine adjustment of axial distances by the trial-and-error technique. One of such conventional ways of fine adjustment of axial distances between lens groups is disclosed in, for example, Japanese Unexamined Patent Publication No. 2002-286993.
Recent marked development of compact cameras strongly presses a demand for more compactness as well as a demand for a reduction in production cost. However, the conventional distance adjustment mechanism comprises a number of mechanical parts including adjuster rings and adjusting screws and requires a long time for the distance adjustment during assembling the taking lens while makes it possible to accomplish a fine adjustment of distances.